Bag opening and emptying machine

ABSTRACT

A machine for slitting and emptying bags containing free flowing particles of material. It has a mechanically driven belt conveyor that transports vertically oriented bags along the first portion of a predetermined path. A rotary or stationary knife is positioned at the end of the first portion of the path for slitting the bottom portion of each bag as it passes thereover. Bag flatteners are positioned to extend inwardly over the conveyor from its opposite lateral edges to guide and compress the bags as they approach the knife and also to provide support for keeping the bags vertically oriented. Bag ejector means in the form of pinch rollers are positioned immediately rearwardly of the knife to grip the top edge of the vertically oriented bags and carry them along a second portion of the predetermined path. Mechanical beaters are positioned on laterally opposite sides of the second portion of the predetermined path to aid in emptying all the particles of material in the bags into the hopper that extends along the bottom of the machine.

United States Patent 1191 Lavoie [111 3,811,586 1451 May21, 1974 1 BAG OPENING AND EMPTYING MACHINE [76] Inventor: Gilbert V. Lavoie, 31 1 Elm St.,

' Raynham, Mass. 02767 221 Filed: Feb. 24, 1972 21 Appl. No.: 229,095

52 us. a. 214/305, 198/127 51 Int. c1. B65g 65/04 [58] Field of Search ..214/30s; 193/38; 198/180,

7 [56] References Cited UNITED STATES PATENTS 3,022,912" 2/1962. Vincent "214/305 2,004,349 6/1935 Schwab 193/38 3,148,877 9/1964 Brearley.l..-...- 271/52 FOREIGN PATENTS OR APPLICATIONS 1,221,150 I 7/1966 Germany 214/305 I OTHER PUBLICATIONS IBM Technical Disclosure Bulletin, J. N. Olson et al., v01.- 12, No. 7, 12/1969. 8

Primary Examiner-Robert G. Sheridan Assistant Examiner-Lawrence J. Oresky Attorney, Agent, or Firm-Barlow & Barlow 57 ABSTRACT A machine for slitting and emptying bags containing free flowing particles of material. It has a mechanically driven belt conveyor that transports vertically oriented bags along the first portion of a predetermined path. A rotary or stationary knife is positioned at the end of the first portion of the path for slitting the bottom portion of each bag as it passes thereover. Bag flatteners are positioned to extend inwardly over the conveyor from its opposite lateral edges to guide and compress the bags as they approach the knife and also to provide support for keeping the bags vertically oriented. Bag ejector means in the form of pinch .rollers are positioned immediately rearwardly of the knifeto grip the top edge of the vertically oriented bags and carry them along a second portion of the predetermined path. Mechanical beaters are positioned on laterally opposite sides of the second portion of the predetermined path to aid in emptying all the particles of material in the bags into the hopper that extends along the bottom of the machine.

4 Claims, 4'Drawing Figures BAG OPENING AND EMPTYING MACHINE BACKGROUND OF THE INVENTION muchmanual labor, is expensive, and much of thematerial is left in the sacks. More recently machines of a semiautomatic nature have been developed for applications where hundreds and even thousands of bags need to be emptied during a day. These machines have all been designed toreceive the bags in a horizontal orientation. In most of these the bags are impaled on stakes'sticking out of the machine while rotary cutting knives cutthe bag in half. The bags are then rocked, ro-

tated, shook, etc.; to empty their contents into a hopper beneath the machine. In-some of these machines the bags areremoved by complicated bag ejectormechanisms while with the remaining machines it is necessary to remove the empty bags manually. Also m'ostof the bag opening and emptying machines do-not have a cover or enclosure to prevent the dustof the material in the bags from polluting the surrounding air, to prevent settling of the dust on surrounding equipment, or to prevent the health hazard of inhaling the dust particles from the bags.

SUMMARY or THE INVENTION Applicant's novel bag opening and emptying ma-' 'chine operates to continuously receive, open, empty and discard the empty bags in an automated operation once the'bags havebeen placed upon the belt conveyor of the machine in a vertical orientation. The mechan- -i sed conveyor initiallytransports the bags along the first portion of a predetermined path. A rotary or stationary knife is positioned at the end of the first portion which slits the bottom portion of each bag as it passes thereover. Bag flatteners are positioned to extend inwardly over the conveyor from its opposite lateral edges to guide and compress-the bags as they approach the knife and to also provide supportfor keeping the bagopening andemptying machine will now be debags vertically oriented. After the forward end of the bags passes over the rotary knife the top edge of the bag is gripped by the bag ejector means. The bag ejector means is comprised of a series of pinchroller's that are mechanically driven to carry the bags along the sectight to eliminate air pollution and its health hazard.

Since the contact parts of the machine, with exception of the rotary knife, come in contact only with the paper bag, the machine has theability to be manufactured'for sanitary .operations, and it may be readily cleaned between products. Additionally optional devices such as bagbalers,.bag shredders, or an additional conveyor may be attached to the end of the machine to collect the empty bags as they are ejected.

It is an object of the invention to produce a bag opening machine capable of continuously receiving. full bags, emptying them, and then ejecting them automatically.

It is also an object of the invention to provide a machine which assures rapid and complete emptying of the bags.

Another object of the invention is to provide a machine which is-simple and economical in construction and reliable in operation.

Another object of the invention is to provide bag opening structure which is automatic and in an enclosure to prevent dusting during the opening and emptying of the bags.

DESCRIPTION OF THE DRAWINGS DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to FIGS. 1 and 2, the applicants novel scribed. The machine is generally designated by the numeral 10. Its basic components are conveyor unit 15, rotary knife cutting unit 35, bag flattener unit 45, bag ejector unit 72, and bag beater unit 92.

Conveyor unit I5 initially receives the full bags that are. to be emptied and transports them along the first portion of a predetermined path of travel. The unitis comprised of a metal shell housing 16 over which belts 17 pass with the shell providing the strength to support the weight of the bags. The belts form closed loops having one of their ends passing around pulleys 18 .mounted on shaft 19 and their other ends passing around pulleys 20 on shaft 21. Sprocket gear 22 mounted on shaft 21 transmits motion to the conveyor belts through chain 23 which is in turn driven by sprocket gear 24. Motor 26 is connected through standard gearing to sprocket gear 24. An additional partof conveyor unit 15 is auxiliary conveyor belt 27 which is also of the closed loop type and it passes around pulley 28 mounted on shaft 29. A slave drive unit 30 comprising sprockets 31 and 32 mounted on shafts 19 and 29 respectively, and chain 33 transmit motion to auxiliary belt 27.

Rotary knife unit 35 is mounted in the machine forward of conveyor'unit 15. Its rotary knife 36 extends inwardly into slot 34 formed at the forward end of metal support shell 16 'to slit the bottom of the bags passing over the conveyor unit before they pass off the end of the conveyor belts. The knife is mounted on shaft 38 which has sprocket 39 mounted at its outer end. Chain 40 passes around sprockets 39 and 41 to transmit the power from motor 42 that rotates the knife. r

The structure that compresses the bags and guides them into proper alignment with the rotary knife and bag ejector means is bag flattener unit 45. It also provides supporting structure to keep the bags vertically oriented so that the top of the bags are properly engaged by the bagejector unit after the bags have been slit. The bag flattener unit is comprised of two identical units each having a metal shell 46, a pulley 47 mounted on shaft 48, a pulley 49 mounted on shaft 50, and a continuous loop belt 51. Extending upwardly from each metal shell 46 are a pair of rods 53 and 54 that are secured to cross members 56 and 57. Rods 53 may be pivoted in apertures 58 while rods 54 may be moved transversely inwardly and outwardly in slots 59 to vary the width of the bags being processed. Rods 54 can be fixedly secured to cross member 57 in a set position by any standard clamping means desired. The drive for belts 51 is transmitted to sprockets 61 by chains 62 from sprockets 63. Sprockets 63 in turn are mounted on shafts 64 which have additional sprockets 66 mounted thereon and one of the sprockets 66 receives its rotational movement from chain 68 which is indirectly connected to motor 70 which also drives the bag ejector unit 72. A shaft 64is driven by motor 70, gear 69 meshes with gear 71 on shaft 64 to provide a simultaneous drive for both belts 51 of the bag flattener unit.

As the bags have their bottoms slit their contents start to discharge and their forward edge approaches the second portion on their predetermined path of travel. At this point the top edge of the bag is gripped by a series of pinch rolls 74. These pinch rolls pass the bags along over top of hopper 80 while the remaining contents of the bags are emptied. The drive for rolls 74 also comes from motor 70 and starts with sprocket 82 driving chain 83 which in turn rotates sprocket 84 on shaft 85. It will be remembered that it was through sprocket 87 also mounted on shaft 85, that chain 68 drivesthe bag flattening unit as .was previously described. The individual rolls 74 are d'rivingly connected to rotate simultaneously through chains passing around sprocket gears that are also mounted on the same shafts as the pinch rolls.

While the bags are traveling through the bag ejector unit they are continuously pounded by the heaters 90 of bag beater unit 92. Beaters extend downwardly from laterally opposite sides ofthe bags as they pass through.

The heaters 90 are attached to the end of shafts 94 and are rotationally driven by belt 95 which passes around pulley 96 mounted on shaft 94 and pulley 97 which is mounted on the shaft of motor 98. Sincethe opening and emptying operations are performed within housing 100, air pollution to the surrounding area-is prevented and a dust free work area is provided for the workers. As the bag leaves the last rollers of the bag ejection unit it may pass to an auxiliary unit 110 which could be a bag shredder, bag hinder. or any other type of unit designed to dispose of the bag.

As seen in FIGS. 3. and 4, an alternative bag guide means 120 is illustrated for properly aligning the bags with the rotary knife. This guide means is comprised of a pair ofguide bars 122 having tips 123 that flare laterally outwardly and which have vertically adjustable support posts 125. The alternative guide means can be used when the bags contain material that does not slump enough to necessitate the use of the bag flattener unit.

As various changes may be made in the form. construction and arrangements of the parts herein, without departing from the spirit and scope of the invention and without sacrificing any of its advantages, it is to be understood that all matter herein is to be interpreted as illustrative and not in any limiting sense.

What is claimed is:

l. A bag opening and emptying machine comprising:

spaced conveyor means moving in generally a horizontal plane for moving bags along a first portion of a predetermined path,

cutting means positioned between said spaced conveyor means at the forward end of the first portion of the given path for slitting the bottom portion of each bag,

generally vertically extending guide means for guiding vertically oriented bags on the conveyor means as they travel along said first portion of the given path toward said cutting means,

receiver means positioned to receive the contents of the bags after their bottom has been slit,

bag transfer and ejector means above the receiver means and beyond the cutting means at a location to grip the bag after it has started to empty thereby facilitating the gripping of the bag, said transfer and ejector means comprising a plurality of spaced substantially identical pairs of opposed rolls having generally vertical axes of a length to extend along a minor portion of the uppermost vertical extent of a bag to be gripped for intermittently gripping the top edge of said vertically oriented bags and carry them along a second portion of the given path, and a beater means above the hopper means and below the vertical extent of said ejector means to engage the bag.

2. A bag opening and emptying machine as recited in claim 1 wherein said guide means comprise a pair of vertically adjustable bag guide rails with one each mounted on the opposite sides of said conveyor means and in advance of said cutting means.

3. A bag opening and emptying machine as recited in claim 1 further comprising an enclosed housing to prevent pollution of the air surrounding the machine when the bags are opened and emptied into the hopper.

4. A bag opening and emptying machine as recited in claim 1 wherein said guide means comprise engaging portions spaced a distance less then the size of the bag engaged. said means including conveyor belts passing around vertically oriented pulleys and have a support shell-within the loop of the belts to provide support strength to keep the bags vertically oriented. 

1. A bag opening and emptying machine comprising: spaced conveyor means moving in generally a horizontal plane for moving bags along a first portion of a predetermined path, cutting means positioned between said spaced conveyor means at the forward end of the first portion of the given path for slitting the bottom portion of each bag, generally veRtically extending guide means for guiding vertically oriented bags on the conveyor means as they travel along said first portion of the given path toward said cutting means, receiver means positioned to receive the contents of the bags after their bottom has been slit, bag transfer and ejector means above the receiver means and beyond the cutting means at a location to grip the bag after it has started to empty thereby facilitating the gripping of the bag, said transfer and ejector means comprising a plurality of spaced substantially identical pairs of opposed rolls having generally vertical axes of a length to extend along a minor portion of the uppermost vertical extent of a bag to be gripped for intermittently gripping the top edge of said vertically oriented bags and carry them along a second portion of the given path, and a beater means above the hopper means and below the vertical extent of said ejector means to engage the bag.
 2. A bag opening and emptying machine as recited in claim 1 wherein said guide means comprise a pair of vertically adjustable bag guide rails with one each mounted on the opposite sides of said conveyor means and in advance of said cutting means.
 3. A bag opening and emptying machine as recited in claim 1 further comprising an enclosed housing to prevent pollution of the air surrounding the machine when the bags are opened and emptied into the hopper.
 4. A bag opening and emptying machine as recited in claim 1 wherein said guide means comprise engaging portions spaced a distance less then the size of the bag engaged, said means including conveyor belts passing around vertically oriented pulleys and have a support shell within the loop of the belts to provide support strength to keep the bags vertically oriented. 